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I have now had some seat time around the track, my suspension and breaks are not stock, and I have a surplus of tires ... so time for some power!!

Got a winter beater so I can still get to work:

2 years go a buddy of mine gave me a K04 turbo, looked into it and turned outto be too small, looked into it further and decided the 6cyl would benifit from 2 turbos instead.
Happily the S4 guys ditch their K03's regularly. They may have been too small for the 2.7V6 but they fit the 2.5l ... better.

This build somewhat started in the fall when I was rebuilding my head and changing the timing belt.
I replaced the valvesprings, decked the head, polished the combustion chamber and gasketmatched the exhaust ports.Before:

After:

Left is polished, Right is stock

I figured I would get the build off to a running start by starting it over the Holidays....lol didnt really happen but here is what is done so far:

In the beginning:

End of Day 1: Have the front end apart and rad out (yes the pile of garbage just got pushed out of the way lol)

End of Day 2:Intake, Exhaust, Oil cooler are gone

Day 3: Have to make sure the Turbo's fit somehow... Managed to rotate the compressor housing to be able to clock it better in the engine bay. I'll end up dealing with the oil and Cooling lines after, as long as I have access to route the lines/fittings. The rear turbo will be sitting close to stock but the front one will be rotated almost 180 deg (top facing down), so I should be able to swap the oil drain with the inlet..TBD

There are 2 ways I am thinking about placing the rear turbo

Way 1: works better with exhaust flow into the turbo, but I think I will have problems with packaging the exhaust from the front turbo and the exit of this one. Fluid lines wil be easier to fit though and a gravity drain I dont think will be a problem

Yah I have seen a bunch of those, the reason I chose the position that I did is so I can have a straight section at the beginning of my downpipe. I'm going to try an build a divider into the tube, separating the wastegate and turbine exit. I have a chineese turbo I'm going to use for some testing to see if its worth having a diffuser at the turbine exit as well (read something on power generation turbines).

here is a pic I had found from what I think is an Alpina done M20 twin turbo if there was such thing...Cant remember where I got this pic

You're a brave man... The K03's spool very quick on a 2.7T... My S4 made 386 AWTQ @ 20 psi @ 2800 RPM... on a stock M20 that will pretzel your rods if you try that for sure. So that would be well over 400 WTQ on a 2WD car.

My 0.2 cents on turbo placement is make sure you can actually assemble it once its all in the car, home made systems that arent thought out can be real ****y, especially TT. I don't think you will have an BC issues as they're IG turbos.

Have you thought about how your going to plumb the coolant for them? Also on the oil return of the lower turbo, you were mentioning a scavenge system, you will probably need to have the turbo drain to a small reservoir then have the scavenge from there (this could hang right off the drain fitting).

You didn't mention what your going to do with the HG. Any thoughts on that yet?

You're a brave man... The K03's spool very quick on a 2.7T... My S4 made 386 AWTQ @ 20 psi @ 2800 RPM... on a stock M20 that will pretzel your rods if you try that for sure. So that would be well over 400 WTQ on a 2WD car.

Make sure you have good control over your boost.

I'm looking to leave enough space so I can aslo switch to K04's if i so choose

I got a spare motor waiting and I was thinking about building a 2.7 if needed... hoping it holds up ok but well see when its finished, the front ends will be removeable now so should be even easier to replace motors I guess.

The Goal is to only make 300hp, so when can drive the tits off that, and its reliable enough i'llstart adding. I have a megasquirt for now to control the boost but when this is done the next thing I'm spending money on (apart from gas) is a higher quality ECU..

Quote:

Originally Posted by Yamahammer

My 0.2 cents on turbo placement is make sure you can actually assemble it once its all in the car, home made systems that arent thought out can be real ****y, especially TT. I don't think you will have an BC issues as they're IG turbos.

Have you thought about how your going to plumb the coolant for them? Also on the oil return of the lower turbo, you were mentioning a scavenge system, you will probably need to have the turbo drain to a small reservoir then have the scavenge from there (this could hang right off the drain fitting).

You didn't mention what your going to do with the HG. Any thoughts on that yet?

I was going to V-band the crap outta my exhaust system so hoping it should be easy enough to assemble.. the reason its taken this long to get an update is so I can plan the front end properly (and work ).. havent though about plumbing the coolant yet reallythough. I was considering taking it from the drainplug but it probably wont flow enough.

I might try knocking in the firewall a bit so I can raise that turbo but I havent measured how much height I need yet. Makes life easy if I dont need a scavenge period.

Head Gasket will stay stock for now, I'll tune the car with this motor and if it doesnt last it was a cheap way to learn. I would rather wear this motor with knocking and such during tuning then one I built. But I do have ARP studs I was going to put in as a small amount of insurance.

havent gotten much done lately but hopefully I'll have more time this weekend... whats been done since is:

a whole lot of cutting:

Fitted the flanges for the first time
here are the other 2:

And after a whole bunch of measuring to almost the right size

looking to get some steel this week and put somthing like that together some time this weeknd (I really hope it looks nothing like the pink frame because that looks terrible lol). I'm also hoping to keep the "hood tray" because where else would I put my tools, just another challenge really.

As you can see the rad is leaning forward (might have to cut the inner headlight mount a bit) I'm looking to mount the intercooler just infront and on the bottom, and the oil cooler ontop of that. Hopefully with an electric fan I'll have enough room to put a proper shroud out the hood

I'm looking to leave enough space so I can aslo switch to K04's if i so choose

I got a spare motor waiting and I was thinking about building a 2.7 if needed... hoping it holds up ok but well see when its finished, the front ends will be removeable now so should be even easier to replace motors I guess.

The Goal is to only make 300hp, so when can drive the tits off that, and its reliable enough i'llstart adding. I have a megasquirt for now to control the boost but when this is done the next thing I'm spending money on (apart from gas) is a higher quality ECU..

K04's are only marginally bigger then K03 as a whole so you probably won't have much issue upgrading down the road if you make everything correctly. All the flanges, etc are the same and the turbo will rest in the same spot.

As for 300hp, that shouldn't be an issue at all even on K03's... of course the M20 doesn't flow anywhere near as well as the 2.7 or any modern 4V motor two K03's from the 2.7 are still more then enough for that and more power wise.

But like I said, they will probably come on very hard, so you'll want to keep the TQ spike at low RPM under control to keep your rods straight

K04's are only marginally bigger then K03 as a whole so you probably won't have much issue upgrading down the road if you make everything correctly. All the flanges, etc are the same and the turbo will rest in the same spot.

As for 300hp, that shouldn't be an issue at all even on K03's... of course the M20 doesn't flow anywhere near as well as the 2.7 or any modern 4V motor two K03's from the 2.7 are still more then enough for that and more power wise.

But like I said, they will probably come on very hard, so you'll want to keep the TQ spike at low RPM under control to keep your rods straight

So its about time I posted something... had my heaters going in my newly insulated Garage...mmm 7 degrees ... is magic when its -15 outside lol

Onto the Reconstruction!!

As I'm working on the front end I pull out my Aluminum rad.... got to test fit it right?

Turns out a year ago I bought the M3 Rad... whoops ... its smaller in almost every way. I contemplated using it at one point.. the M3 was a 2.5L right? so how different could the cooling be.. but having the Turbo's I bailed on that idea and picked up a used one

But it didnt fit!!!

So I learned to weld Aluminum...

Holy Balls that difficult!!!

Then I cut up my Rad

it took 4 passes to get enough of the oxidization and crap off the old aluminum dispite my best efforts to clean it.. and I had to grind the bead at the bottom because it was too wide still.

With the assumption that my weld wont hold I've made it so I can also fit the stock rad in

This is what I'm using for the hood tray... also to show how much easier it is to weld steel..

Today I was working on the holes for the vertical parts of the frame. Welded 2 M10 nuts into the frame rail and notched it a bit to make room for the stock rad if needed. As an added bonus one of the nuts warped in position and I'll only have one screw able to go through .. yay weight savings?

soo with everything bolted in..

Next up is the intercooler mounting which will probably be separate from the frame I've made. My intercooler has 2 mounting holes ontop and bottom, so I'm thinking I'll strap the bottom ones to the rad frame, and put a bar across the top of the frame rails, to mount to the top mounting holes. I know the intercooler looks low ... and it is... but its still 2" above the oil pan ... I think.. So i''ll be dropping the car tomorrow to check

Heres a teaser ... because I'm getting bored of working on the front frame lol

Got this at the autoshow for when its done

next step is to mount the intercooler, then oil cooler, mount the hood, all the brackets, THEN I can start on the manifolds.

One thing I will have to get rid of though are the fog lights

the intercooler piping will take the space of the brake ducts ... and I need those so I'll prob move them over to where the fog lights are.. unless somebody has a genious suggestion??